Which word best describes "vigor"?

The word "vigor" is best described as relating to energy and vitality. It embodies a sense of robust health, physical strength, and energetic activity. When someone possesses vigor, they exude enthusiasm and are often seen as dynamic and lively. This term is frequently used to convey a strong, spirited approach to tasks or challenges, indicating that an individual is fully engaged and enthusiastic.

Words like weakness, calmness, and indifference contrast with the essence of vigor. Weakness implies a lack of strength and energy, while calmness suggests a state of tranquility, often devoid of the dynamic energy associated with vigor. Indifference reflects a lack of interest or concern, which does not align with the active and vigorous nature implied by the correct choice. Therefore, the choice that encapsulates the meaning of vigor most accurately is the one that emphasizes energy and vitality.